An object-relational database can be a relational database system that is programmed, extended, or customized to store, query, and retrieve data objects. In an object-relational database, objects, classes, and relationships between objects or between classes can be represented in database schemas that define tables and relationships between tables. Compared to a conventional relational database where relationship between data is usually flat, relationship between objects in an object-relational database can be hierarchical. Accordingly, when handling deletion of an object, an object-relational database can encounter situations where the object to be deleted has one or more children objects. Conventionally, an object-relational database system can use explicit recursive delete or reference counting to handle deletions to ensure that when an object is deleted, descendants of the object are also deleted.